Re: Oracle to Postgres

Thank you, Ron!

On Fri, Jul 12, 2024 at 11:12 PM Ron Johnson <ronljohnsonjr(at)gmail(dot)com>
wrote:

> We did the safe thing, and sized the RDS Postgresql the same as the Linux
> system running Oracle 12. Turned out to be massively over-sized.
>
> Your mileage will *certainly* vary, though.
>
> PG12 used a lot less CPU and RAM than PG12.
> On Thu, Jul 11, 2024 at 9:45 PM Sam Stearns <sam(dot)stearns(at)dat(dot)com> wrote:
>
>> Thanks for all the advice on the conversion stuff!
>>
>> For the resource sizing I was chasing more CPU and memory analysis then
>> giving recommendations on right-sizing the VM.
>>
>> On Fri, Jul 12, 2024 at 10:53 AM Ron Johnson <ronljohnsonjr(at)gmail(dot)com>
>> wrote:
>>
>>> On Thu, Jul 11, 2024 at 8:02 PM Sam Stearns <sam(dot)stearns(at)dat(dot)com> wrote:
>>>
>>>> Howdy,
>>>>
>>>> We have a project to migrate our Oracle databases that are hosted on an
>>>> Oracle Database Appliance to Postgres hosted on a Linux VM. Questions:
>>>>
>>>>
>>>> 1. Is there a tool out there that we can use to analyze resource
>>>> sizing on the Appliance that will give resource sizing recommendations for
>>>> the VM?
>>>>
>>>>
>>> The appliance doesn't tell you how much space your database uses???
>>>
>>> Anyway, we converted an 8TB on-prem Oracle 12 db (heavy on CLOBs) to RDS
>>> Postgresql 12; the resulting db was about 6TB. I'm sure that vanilla PG
>>> would be about the same size (or smaller now, since compression on
>>> dupes-allowed b-tree indices is much better now than in PG 12).
>>>
>>>
>>>>
>>>> 1. Is there a schema conversion tool or similar out there that we
>>>> can use to convert Oracle ==> Postgres?
>>>>
>>>>
>>> As Keith said, Google is your friend.
>>>
>>> That's how I found ora2pg, which we used in our conversion project (for
>>> the data only; someone had to rewrite all the stored procedures).
>>>
>>> If you use ora2pg, remember to tell it to convert all of the
>>> NUMERIC(38,0) columns to BIGINT.
>>>
>>>>
>>
>> --
>>
>> *Samuel Stearns*
>> Lead Database Administrator
>> *c:* 971 762 6879 | *o:* 503 672 5115 | DAT.com
>> [image: DAT]
>> <https://www.dat.com/?utm_medium=email&utm_source=DAT_email_signature_link>
>>
>

--

*Samuel Stearns*
Lead Database Administrator
*c:* 971 762 6879 | *o:* 503 672 5115 | DAT.com
[image: DAT]
<https://www.dat.com/?utm_medium=email&utm_source=DAT_email_signature_link>